1. Field of the Invention
The present invention relates to the field of surgical instrumentation. More particularly, the present invention relates to surgical instruments which are used to remove an implanted catheter from a patient.
2. Background
Catheters are surgically implanted in a patient when it is necessary to provide medications, blood products, liquid food, etc. to the patient for a significant amount of time. It is essential is such cases that the implanted catheter is anchored within the patient. One approach to anchoring the implanted catheter is the placement of a permeable member of the implanted catheter inside the patient to promote tissue ingrowth within the permeable member. Typically, the permeable member is either a catheter tube or a cuff affixed around the catheter tube as described in U.S. Pat. Nos. 4,266,999, and 4,405,313, hereby incorporated by reference. A commercial example of a cuff is a Dacron(copyright) cuff 12 of a Cook TPN(trademark) (Total Parenteral Nutrition) single lumen catheter 10 as shown in FIG. 1. Referring to FIGS. 1 and 2, an illustrative implantation of catheter 10 involves surgically creating a subcutaneous tunnel 23 through a skin 20 and a tissue 21 of the patient to a blood vessel 22 of the patient, inserting a distal end 11a of a catheter tube 11 of catheter 10 through subcutaneous tunnel 23 into blood vessel 22, and positioning cuff 12 midway between a skin entry point 20a and a blood vessel entry point 22a. Subsequently, tissue adhesion occurs along an interface A of cuff 12 and tissue 21 to promote ingrowth of a portion 21a of tissue 21 within cuff 12 as shown in FIG. 2. As a result, portion 21a of tissue 21 anchors catheter tube 11 within the patient. Upon completion of the treatment, catheter tube 11 must be removed from the patient. Presently, a cutting instrument, e.g. a scalpel, is utilized to dissect cuff 12 away from tissue 21. Referring to FIG. 3, the drawbacks associated with the utilization of a cutting instrument are the concurrent dissection of portion 21a and a portion 21b of tissue 21 away from tissue 21, the difficulty in minimizing the amount of portion 21b of tissue 21 that is dissected with cuff 12, and the promotion of a substantial amount of bleeding at 24 throughout subcutaneous tunnel 23.
The present invention provides a new and unique surgical instrument for removing an implanted catheter which operates to extract tissue ingrowth from a permeable member of an implanted catheter. The surgical instrument is easy and convenient to use, and overcomes the aforementioned drawbacks associated with the utilization of a scalpel to dissect tissue adhering to the permeable member of the implanted catheter.
As shown in the following description of the preferred embodiments, a surgical instrument is operable to extract a tissue ingrowth out of a permeable member of a catheter implanted in a patient by forcibly pulling the tissue ingrowth out the permeable member. The surgical instrument comprises a first extracting component including a first wedge having a blunted leading edge, and a second extracting component including a second wedge having a blunted leading edge. The extracting components are pivotally coupled to move the wedges to a closed position or to an open position. The blunted leading edges of the wedges are sized and shaped to be lodged adjacent an adhesion interface of the permeable member and the tissue of the patient when the wedges are in the closed position. As a result, the wedges can be pivotally moved to the open position to forcibly pull the tissue ingrowth out of the permeable member.
It is an object of the present invention to provide a surgical instrument for removing a catheter implanted within a patient which is operable to forcibly pull tissue ingrowth out of a permeable member of the catheter without any deliberate dissection of the permeable member away from the tissue of the patient.
It is another object of the present invention to provide a surgical instrument for removing a catheter implanted within a subcutaneous tunnel of a patient which minimizes the amount of blood induced throughout the subcutaneous tunnel as the catheter is being removed.
These and other objects and advantages of the present invention will become more apparent from a review of the following description of the preferred embodiments.